Down regulation of Qa gene expression on drug-modified tumor cells

Mouse leukemia, L1210, strongly enhances its immunogenicity following in vivo treatment with 5-(3-3'-dimethyl-1-triazeno) imidazole-4-carboxamide (DTIC). Previous experiments have shown that transformed cells elicit a cell-mediated response accountable for rejection and resistance to a subsequent injection of parental tumor into a syngeneic host. L1210 expresses classical H-2 class I molecules, and since it has been shown that DTIC treatment does not modify the expression of these molecules, this is a suitable model to study nonclassical class I antigens, such as Qa2 glycoproteins, and their potential role in tumorigenicity.